Answer
$g(x)=x^4+2$ and $f(x)=\sqrt{x}$
The domain of $h$ is $\mathbb{R}$
Work Step by Step
If we set $g(x)=x^4+2$ and $f(x)=\sqrt{x}$, then:
$f(g(x))=\sqrt{x^4+2}$
The domain of $h$ is $\mathbb{R}$ (because the inside of the radical is never negative).